US refiners pushed utilization near 93% in early May as record exports and tight global fuel supplies boosted refinery demand, Kpler said in a Monday note.
Kpler said strong refining margins, lighter maintenance schedules, and rising global demand for refined fuels are keeping US downstream operations in max-output mode.
The latest Energy Information Administration data showed refinery utilization running about 4 percentage points above normal seasonal levels during the first week of May, despite some unexpected outages.
Kpler expects refinery throughput to stay above 16.5 million barrels per day during May, while second- and third-quarter runs could average between 16.5 million b/d and 16.7 million b/d.
Refinery closures across Europe and parts of the US, along with reduced refinery runs east of the Suez Canal, have increased dependence on Atlantic Basin suppliers, the note said.
Kpler said the US and Nigeria's Dangote refinery have become key balancing suppliers for global fuel markets as buyers replace disrupted Middle Eastern product flows.
The report said sustained high refinery utilization is increasing pressure on operations and could raise the risk of additional outages during the summer driving season.
Kpler pointed to recent disruptions and maintenance events at BP's Whiting refinery, Valero's Port Arthur refinery, and Exxon's Baytown refinery as signs of rising operational strain.
Strong diesel and jet fuel margins, along with improving gasoline cracks ahead of summer demand, continue supporting elevated refinery runs, particularly along the US Gulf Coast, Kpler said.
US refiners are also processing more domestic light crude oil, with the weighted-average API gravity of their feedstock rising about 2.2 points since 2015 as shale output expands.
US clean product exports averaged about 3.3 million b/d since March, up from roughly 2.8 million b/d during the first two months of 2026 and about 2.6 million b/d in 2025, according to Kpler.
The report said major US fuel inventories dropped from around 440 million barrels on March 3 to roughly 385 million barrels by May 9, pushing stocks to five-year lows after a nearly 55-million-barrel draw over 10 weeks.